<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>棋盘</title>
    <style>
        .con {
            height: 450px;
            width: 450px;
            display: flex;
            border: 5px black solid;

        }
        .black {
            width: 150px;
            height: 150px;
            background-color: black;
        }
        .white {
            width: 150px;
            height: 150px;
            background-color: white;
        }
    </style>
</head>
<body>
    <div class="con"> 
        <div>
            <div class="black"></div>
            <div class="white"></div>
            <div class="black"></div>
        </div>
        <div>
            <div class="white"></div>
            <div class="black"></div>
            <div class="white"></div>
        </div>
        <div>
            <div class="black"></div>
            <div class="white"></div>
            <div class="black"></div>
        </div>
    </div>
    
    
</body>
</html>